"I believe that we have attracted a rising star early in his career, and he will assume the post of music director at about the same age as Ormandy and Muti," said Worley. "And I believe that continuity is important to building audiences. It is certainly my hope that he will lead this orchestra for a very, very long period of time - I hope a decade or more."
The offer to the boyish, aerobic conductor - whose name is pronounced Yah-NEEK Neh-ZAY Say-GUN, but is commonly shorthanded to YNS - came after only two visits to Verizon Hall, in 2008 and 2009.
Opinions vary, as they do on most conductors, but Nézet-Séguin is considered something of a catch, and has been hailed as an important starter by even fastidious critics.
"Although he is not as flamboyant as the Venezuelan Gustavo Dudamel, the pair are increasingly mentioned in the same breath as leaders of their generation," wrote London critic Norman Lebrecht for Bloomberg recently.
The new partnership aims to satisfy critical objectives for both parties:
The orchestra captures a winsome, energetic chief and renewed institutional energy after a four-year search dogged by flagging ticket sales; and Nézet-Séguin wins a top job in a first-rank ensemble, which, despite his many prestigious guest appearances, he has not yet landed.
But the move does not come without risk.
What's not clear is whether the young conductor carries enough authority to manage backstage duties such as prickly personnel matters, or whether he has an ear for the ensemble-building workouts required to maintain quality.
Also unknown is whether he will cultivate the orchestra's blended, string-rich personality.
"Sometimes you have to take a risk, and it doesn't feel like a huge risk," said one orchestra player who counts himself a fan. "The risk is that it's only 75 percent of what is hoped for, and the best case is that it's 110 percent."
Offering the job after only two visits means that the orchestra will have made the appointment after less contact with Nézet-Séguin than any other conductor since Leopold Stokowski arrived in 1912, age 30, sight unseen.
Riccardo Muti was already principal guest conductor with several multiple-week appearances by the time he, at age 39, officially succeeded Eugene Ormandy in 1980. The choice of Wolfgang Sawallisch was announced in 1990 after a guest conducting relationship that began in 1966. Though Christoph Eschenbach had not been a recent presence when he was named in 2001, he did have a track record beginning with his debut in 1989.
But the orchestra had few deep relationships to fall back on when Eschenbach and the orchestra announced a separation in 2006.
Simon Rattle was sounded out about the job, but, after signing a contract to take over the Berlin Philharmonic, his agent said that as far as Philadelphia was concerned, "all bets are off."
"He has accepted the invitation from the Berliner Philharmoniker to continue as their chief conductor and music director," said Martin Campbell-White in 2008. "Like any sensible person, he can only have one job at a time."
Vladimir Jurowski, 38, who drew sold-out houses and ardent support from the musicians, was asked early on in the search process whether he would be interested in the job. But he signaled that he was committed elsewhere through 2015. The orchestra has now proposed multiple-week visits and touring with the Russian-born maestro in future seasons, but nothing has been settled.
Nézet-Séguin follows Charles Dutoit, 73, the Swiss conductor who has held some music-director responsibilities but not others in an unusual "chief conductor" contract running through the 2011-12 season.
Though the quality of his performances and close rapport with the orchestra were never disputed, Dutoit divided musicians on the question of whether he should have been given the music director title.
It was a post he clearly would have savored after a three-decade relationship spanning several titles at Verizon Hall, and the orchestra's summers homes in Saratoga Springs, N.Y. and Fairmount Park.
"I was 10 years at the Mann and I will have conducted around 200 different programs at [Saratoga] in the 21 years I will have been there. (Ormandy was there for 19 years!)," Dutoit wrote in an e-mail last week. "But these recent years here in Philadelphia have been the most difficult ones of my entire professional life. The total vacuum in the administration when I started, the recession, the strange attitude of the press and the search committee have all created an unhealthy atmosphere which was often hard to work in.
"I just hope that some day, my tenure here as Chief Conductor will be perceived as more than just an 'interim' conductor.
"It was not easy steering straight in these hard times and I think an extremely high musical level was maintained despite the chaotic times."
After deciding to part ways with Eschenbach, the orchestra set up a search committee of board members, musicians and orchestra administrators in 2007. Rank-and-file musicians were periodically polled for reactions to visiting conductors.
Some musicians were hoping that an overwhelming mandate would gather around a particular aspirant, but others thought the search had gone on long enough.
"Waiting for something to happen" had ceased to be an option, said one musician, "because of the danger of creating an ideal so perfect that no one would ever meet it."
The choice of Nézet-Séguin comes amid unprecedented financial and organizational challenges for the 110-year-old orchestra, which is operating through the support of an emergency bridge fund and grappling with the question of how, and even whether, to maintain an international profile as one of the world's best orchestral ensembles.
The orchestra's latest projections estimate a $1.6 million deficit at the end of the season - perhaps lower if the orchestra can close the gap on raising money for the bridge fund. Worley says he expects the music-director announcement will stimulate generosity. "I certainly hope so and expect so," he said.
Orchestra president Allison B. Vulgamore declined to quantify Nézet-Séguin's compensation. The Orchestra Association paid $1.75 million to Eschenbach in the year ending Aug. 31, 2008, according to tax filings.
With his datebook already crowded, Nézet-Séguin's arrival in Philadelphia will come in phases. In 2010-11, as music-director-designate, he will conduct two weeks here. In 2011-12, the number of weeks will increase to five. In his first season as music director, 2012-2013, Nézet-Séguin will lead up to seven weeks of concerts. In his second and third seasons (2013-14 and 2014-15) he will conduct 15 weeks. He will conduct 16 weeks of concerts in his fourth and fifth seasons (2015-16 and 2016-17). His responsibilities will include subscription concerts, special events, tours and summer appearances.
The appointment of Nézet-Séguin is not necessarily a bellwether of any institutional direction. His career so far has struck a balance between local loyalties and global ambition.
After taking over the second-tier Orchestre Métropolitain du Grand Montréal in 2000, Nézet-Séguin's career accelerated in 2008, when he became music director of the Rotterdam Philharmonic Orchestra and principal guest conductor of the London Philharmonic Orchestra.
A quick series of prestigious debuts followed: the Philadelphia Orchestra (only his second U.S. orchestral debut, and his first with one of the traditional "Big Five"), the Salzburg Festival and the Metropolitan Opera.
"The singers benefited immensely from the work of the rising . . . Canadian conductor Yannick Nézet-Séguin, in his Met debut, who led a bracing, fleet and fresh account of the score, although he started the rousing prelude at a breakneck, frenetic tempo," wrote New York Times critic Anthony Tommasini of the conductor's Carmen on New Year's Eve 2009.
(The Met was rewarded for its debut of Nézet-Séguin: Jacqueline Desmarais, a managing director of the Met Opera Board and wife of Paul Desmarais, Sr., one of the 10 richest Canadians, decided to sponsor the new Carmen production upon learning that Nézet-Séguin would conduct it. Now he is signed up for one production in each of the next several seasons.)
"Now and then, as in his vibrant performance of Carmen at the Met, Mr. Nézet-Séguin let youthful enthusiasm get the better of him," wrote Tommasini in another review, this one of an appearance with the Rotterdam Philharmonic Orchestra. "But who cared if he sometimes pushed the playing to extremes, when the music making was so in the moment and fresh?"
"If there's one gift I have from nature," the conductor told the Guardian, "it's a sort of limitless energy. I always find more - I don't know how."
Some music industry leaders privately posit that it's too much too soon, that by spreading himself so thin, Nézet-Séguin isn't giving himself adequate time to develop thoughtful interpretations.
But the pace shows no sign of slowing. He has debuts set for La Scala Milan and the Royal Opera House Covent Garden in 2010-11 and 2011-12, respectively.
He turned down a last-minute offer to debut with the Berlin Philharmonic when the date conflicted with his Montréal orchestra's Christmas concerts, but has a make-up debut with that ensemble set for October. He is scheduled for a first Chicago Symphony Orchestra outing in January.
Born March 6, 1975, in Montréal into a family of educators, the conductor was first named Yannick Séguin but at age 18 augmented his father's surname with his mother's.
His mother, Claudine - who still manages many of her son's affairs, and who sings under his baton in the chorus of his Montréal orchestra - told a Dutch newspaper that he announced his decision to be a conductor at 10.
After taking up piano, he expanded his studies into conducting, chamber music and composition at the Conservatoire de musique du Québec à Montréal, and later attended rehearsals and performances of the revered Carlo Maria Giulini. He spent two summers at Westminster College of the Arts in Princeton studying choral conducting, and cites Giulini and Dutoit (music director of the Montréal Symphony from 1977 to 2002) as his chief inspirations.
"Dutoit would introduce pieces and be very accessible, and that had a big impact on me as a little boy," the conductor told Toronto's Globe and Mail. "If it had not been for this, I would maybe never have been a conductor."
With grand gestures and a jovial mien - in rehearsal he likes to sing instrumental parts out loud, in falsetto - Nézet-Séguin inspires some musicians and strikes others as limited.
"He's got a youthful personality and is trying to be too funny or clever too much of the time," said one Metropolitan Opera orchestra player who did not want to be identified. "Like many young conductors, he seems to take faster tempi too fast. He is not a conductor I would like as a steady diet."
Alain Cazes, a tuba player and founding member of the Orchestre Métropolitain du Grand Montréal, says Nézet-Séguin "has this ability to communicate his perspective to the orchestra, and his perspective becomes ours. He creates unity of artistic perspective - tonal unity, unity of phrasing. He's extremely clear."
Cazes, who has played with Nézet-Séguin for 11 years, says he has great humility and a non-authoritarian demeanor.
"What's so nice is, each time he makes a small mistake, he says, 'sorry, it's my mistake,' and he starts over again. He gets his authority from who he is and the clarity of what he wants. You know, he's very close to his parents, and it's almost like, 'if you don't like me, I don't care - my mother does.' He doesn't work in a way to get praise or to get love from people. He's just true."
Philadelphia Orchestra bass trombonist and search committee member Blair Bollinger said that it was the young conductor's "energy" and "enthusiasm" that distinguished him.
"It just kept coming back to chemistry," he said. "It's so hard to describe in words."
Off the podium, Nézet-Séguin is fan of Belgian beer, Champagne (Laurent-Perrier demi-sec), Björk, tennis (particularly Rafael Nadal) and Prada.
His repertoire is bound by no particular specialty. On his last visit to Philadelphia, he took the suggestion of Dutoit and led a rare account of Claude Vivier's modern and somewhat wild Orion, with the Franck D Minor Symphony and Brahms' Piano Concerto No. 1.
In 2008 he paired the Tchaikovsky Symphony No. 6 with a Rachmaninoff Piano Concerto No. 2 that threatened to bigfoot piano soloist André Watts.
Next season he returns with Haydn's Symphony No. 100 and Mahler 5 in October, and then, in January, the Mozart Requiem and Debussy's Nocturnes.
As a podium presence, Nézet-Séguin's gestures tend to be so expansively physical they belie his stature; he says he is 5-foot-5.
If it is a drawback, he has found a silencing retort.
"Toscanini," he once pointed out, "was short too."
Contact music critic Peter Dobrin at email@example.com or 215-854-5611. Read his blog at www.philly.com/philly/blogs/artswatch/.